For railroad cars adapted to carry automobiles, it is essential that the cargo be enclosed to protect it from theft of components. Such railroad cars are provided with side walls, a roof spanning the side walls and ends that are closed off by doors or door assemblies. Typically, the railroad cars are designed to have a floor and either one or two intermediate decks supported above the floor for holding the automobiles loaded thereon. The automobiles are driven from platforms at the end of the railroad car onto either the floor or a deck for loading.
The height of the railroad car is a critical matter. Due to limitations (underpasses, tunnels and the like) along the railway, the overall car height is restricted. Especially, in the case of a railroad car designed for three levels, i.e., having two decks supported above the floor, the total height of each automobile is limited by the height of the roof above the floor and by the distance between decks. A savings of two or three inches can be of great significance.
A number of end closure (door) designs are known for railroad cars of the type being discussed. Usually, the door assemblies slide from a closed position to a position along the inside of the side walls on a suitable guide track or rail that is provided adjacent the bottom edges of the door assemblies. The guide rail does not hinder the operation of the door assemblies but rather provides security by restricting their outward movement. Thus, access may not be gained to the railroad car interior by pulling the bottom edges of a door assembly out and away from an end opening.
The guide tracks or rails of the prior art extend upwardly from the floor at the end of the railroad car. This extension, undesirably, takes two or three inches away from the effective distance between floor and intermediate deck of the railroad car. Actually, where it is necessary to bridge the rail with a platform or the like, the floor to deck distance is even further diminished.
It is an advantage according to this invention to provide a railroad car adapted to carry automobiles having end closures with a door bottom guide system that does not diminish the effective distance between floor and intermediate deck of the railroad car while maintaining the security of its contents. A similar result has been achieved, in a pending U.S. application. In Ser. No. 783,943, filed Oct. 3, 1985, a continuous, uninterrupted door guide rail for a railroad car is provided with two depressible, spring-biased rail sections. These rail sections depress into recesses in the railroad car floor when automobile tires travel over them during loading and unloading.